*
* path.c
* portable path handling routines
*
* Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/port/path.c
*
* -------------------------------------------------------------------------
*/
#include "c.h"
#include <ctype.h>
#include <sys/stat.h>
#include "utils/syscall_lock.h"
#ifndef FRONTEND
#include "utils/palloc.h"
#include "utils/elog.h"
#endif
#ifdef WIN32
#ifdef _WIN32_IE
#undef _WIN32_IE
#endif
#define _WIN32_IE 0x0500
#ifdef near
#undef near
#endif
#define near
#include <shlobj.h>
#else
#include <unistd.h>
#endif
#include "pg_config_paths.h"
#ifdef FRONTEND
#include "securec.h"
#include "securec_check.h"
#endif
#ifndef WIN32
#define IS_PATH_VAR_SEP(ch) ((ch) == ':')
#else
#define IS_PATH_VAR_SEP(ch) ((ch) == ';')
#endif
static void make_relative_path(
char* ret_path, size_t ret_path_len, const char* target_path, const char* bin_path, const char* my_exec_path);
static void trim_directory(char* path);
static void trim_trailing_separator(char* path);
* skip_drive
*
* On Windows, a path may begin with "C:" or "//network/". Advance over
* this and point to the effective start of the path.
*/
#ifdef WIN32
static char* skip_drive(const char* path)
{
if (IS_DIR_SEP(path[0]) && IS_DIR_SEP(path[1])) {
path += 2;
while (*path && !IS_DIR_SEP(*path)) {
path++;
}
} else if (isalpha((unsigned char)path[0]) && path[1] == ':') {
path += 2;
}
return (char*)path;
}
#else
#define skip_drive(path) (path)
#endif
* has_drive_prefix
*
* Return true if the given pathname has a drive prefix.
*/
bool has_drive_prefix(const char* path)
{
#ifdef WIN32
return skip_drive(path) != path;
#else
return false;
#endif
}
* first_dir_separator
*
* Find the location of the first directory separator, return
* NULL if not found.
*/
char* first_dir_separator(const char* filename)
{
const char* p = NULL;
for (p = skip_drive(filename); *p; p++) {
if (IS_DIR_SEP(*p)) {
return (char*)p;
}
}
return NULL;
}
* first_path_var_separator
*
* Find the location of the first path separator (i.e. ':' on
* Unix, ';' on Windows), return NULL if not found.
*/
char* first_path_var_separator(const char* pathlist)
{
const char* p = NULL;
for (p = pathlist; *p; p++) {
if (IS_PATH_VAR_SEP(*p)) {
return (char*)p;
}
}
return NULL;
}
* last_dir_separator
*
* Find the location of the last directory separator, return
* NULL if not found.
*/
char* last_dir_separator(const char* filename)
{
const char *p = NULL;
const char *ret = NULL;
for (p = skip_drive(filename); *p; p++) {
if (IS_DIR_SEP(*p)) {
ret = p;
}
}
return (char*)ret;
}
* make_native_path - on WIN32, change / to \ in the path
*
* This effectively undoes canonicalize_path.
*
* This is required because WIN32 COPY is an internal CMD.EXE
* command and doesn't process forward slashes in the same way
* as external commands. Quoting the first argument to COPY
* does not convert forward to backward slashes, but COPY does
* properly process quoted forward slashes in the second argument.
*
* COPY works with quoted forward slashes in the first argument
* only if the current directory is the same as the directory
* of the first argument.
*/
void make_native_path(char* filename)
{
#ifdef WIN32
char* p = NULL;
for (p = filename; *p; p++) {
if (*p == '/') {
*p = '\\';
}
}
#endif
}
* join_path_components - join two path components, inserting a slash
*
* We omit the slash if either given component is empty.
*
* ret_path is the output area (must be of size MAXPGPATH)
*
* ret_path can be the same as head, but not the same as tail.
*/
void join_path_components(char* ret_path, const char* head, const char* tail)
{
if (ret_path != head)
strlcpy(ret_path, head, MAXPGPATH);
* Remove any leading "." in the tail component.
*
* Note: we used to try to remove ".." as well, but that's tricky to get
* right; now we just leave it to be done by canonicalize_path() later.
*/
while (tail[0] == '.' && IS_DIR_SEP(tail[1])) {
tail += 2;
}
if (*tail) {
int rc = snprintf_s(ret_path + strlen(ret_path),
MAXPGPATH - strlen(ret_path),
MAXPGPATH - strlen(ret_path) - 1,
"%s%s",
(*(skip_drive(head)) != '\0') ? "/" : "",
tail);
#ifdef FRONTEND
securec_check_ss_c(rc, "\0", "\0");
#else
securec_check_ss(rc, "\0", "\0");
#endif
}
}
* Clean up path by:
* o make Win32 path use Unix slashes
* o remove trailing quote on Win32
* o remove trailing slash
* o remove duplicate adjacent separators
* o remove trailing '.'
* o process trailing '..' ourselves
*/
void canonicalize_path(char* path)
{
char* p = NULL;
char* to_p = NULL;
char* spath = NULL;
bool was_sep = false;
int pending_strips;
int origin_len = strlen(path);
errno_t ret = 0;
#ifdef WIN32
* The Windows command processor will accept suitably quoted paths with
* forward slashes, but barfs badly with mixed forward and back slashes.
*/
for (p = path; *p; p++) {
if (*p == '\\') {
*p = '/';
}
}
* In Win32, if you do: prog.exe "a b" "\c\d\" the system will pass \c\d"
* as argv[2], so trim off trailing quote.
*/
if (p > path && *(p - 1) == '"') {
*(p - 1) = '/';
}
#endif
* Removing the trailing slash on a path means we never get ugly double
* trailing slashes. Also, Win32 can't stat() a directory with a trailing
* slash. Don't remove a leading slash, though.
*/
trim_trailing_separator(path);
* Remove duplicate adjacent separators
*/
p = path;
#ifdef WIN32
if (*p) {
p++;
}
#endif
to_p = p;
for (; *p; p++, to_p++) {
while (*p == '/' && was_sep) {
p++;
}
if (to_p != p) {
*to_p = *p;
}
was_sep = (*p == '/');
}
*to_p = '\0';
* Remove any trailing uses of "." and process ".." ourselves
*
* Note that "/../.." should reduce to just "/", while "../.." has to be
* kept as-is. In the latter case we put back mistakenly trimmed ".."
* components below. Also note that we want a Windows drive spec to be
* visible to trim_directory(), but it's not part of the logic that's
* looking at the name components; hence distinction between path and
* spath.
*/
spath = skip_drive(path);
pending_strips = 0;
for (;;) {
int len = strlen(spath);
if (len >= 2 && strcmp(spath + len - 2, "/.") == 0) {
trim_directory(path);
} else if (strcmp(spath, ".") == 0) {
if (pending_strips > 0) {
*spath = '\0';
}
break;
} else if ((len >= 3 && strcmp(spath + len - 3, "/..") == 0) || strcmp(spath, "..") == 0) {
trim_directory(path);
pending_strips++;
} else if (pending_strips > 0 && *spath != '\0') {
trim_directory(path);
pending_strips--;
if (*spath == '\0') {
ret = strcpy_s(spath, len, ".");
#ifdef FRONTEND
securec_check_ss_c(ret, "\0", "\0");
#else
securec_check_ss(ret, "\0", "\0");
#endif
}
} else {
break;
}
}
if (pending_strips > 0) {
* We could only get here if path is now totally empty (other than a
* possible drive specifier on Windows). We have to put back one or
* more ".."'s that we took off.
*/
while (pending_strips-- > 0) {
#ifndef FRONTEND
int new_len = strlen(path) + sizeof("../") + 1;
if (new_len > origin_len) {
path = (char*)repalloc((void*)path, new_len);
origin_len = new_len;
}
#endif
ret = strcat_s(path, origin_len, "../");
#ifdef FRONTEND
securec_check_ss_c(ret, "\0", "\0");
#else
securec_check_ss(ret, "\0", "\0");
#endif
}
}
}
* Detect whether a path contains any parent-directory references ("..")
*
* The input *must* have been put through canonicalize_path previously.
*
* This is a bit tricky because we mustn't be fooled by "..a.." (legal)
* nor "C:.." (legal on Unix but not Windows).
*/
bool path_contains_parent_reference(const char* path)
{
int path_len;
path = skip_drive(path);
path_len = strlen(path);
* ".." could be the whole path; otherwise, if it's present it must be at
* the beginning, in the middle, or at the end.
*/
if (strcmp(path, "..") == 0 || strncmp(path, "../", 3) == 0 || strstr(path, "/../") != NULL ||
(path_len >= 3 && strcmp(path + path_len - 3, "/..") == 0)) {
return true;
}
return false;
}
* Detect whether a path is only in or below the current working directory.
* An absolute path that matches the current working directory should
* return false (we only want relative to the cwd). We don't allow
* "/../" even if that would keep us under the cwd (it is too hard to
* track that).
*/
bool path_is_relative_and_below_cwd(const char* path)
{
if (is_absolute_path(path)) {
return false;
} else if (path_contains_parent_reference(path)) {
return false;
#ifdef WIN32
* On Win32, a drive letter _not_ followed by a slash, e.g. 'E:abc', is
* relative to the cwd on that drive, or the drive's root directory if
* that drive has no cwd. Because the path itself cannot tell us which is
* the case, we have to assume the worst, i.e. that it is not below the
* cwd. We could use GetFullPathName() to find the full path but that
* could change if the current directory for the drive changes underneath
* us, so we just disallow it.
*/
} else if (isalpha((unsigned char)path[0]) && path[1] == ':' && !IS_DIR_SEP(path[2])) {
return false;
#endif
} else {
return true;
}
}
* Detect whether path1 is a prefix of path2 (including equality).
*
* This is pretty trivial, but it seems better to export a function than
* to export IS_DIR_SEP.
*/
bool path_is_prefix_of_path(const char* path1, const char* path2)
{
int path1_len = strlen(path1);
if (strncmp(path1, path2, path1_len) == 0 && (IS_DIR_SEP(path2[path1_len]) || path2[path1_len] == '\0'))
return true;
return false;
}
void get_top_path(char *path)
{
char *p = NULL;
if (path == NULL || path[0] == '\0') {
return;
}
for (p = path; !IS_DIR_SEP(*p) && p[0] != '\0'; p++)
;
*p = '\0';
}
* Extracts the actual name of the program as called -
* stripped of .exe suffix if any
*/
const char* get_progname(const char* argv0)
{
const char* nodir_name = NULL;
char* progname = NULL;
nodir_name = last_dir_separator(argv0);
if (nodir_name != NULL) {
nodir_name++;
} else {
nodir_name = skip_drive(argv0);
}
* Make a copy in case argv[0] is modified by ps_status. Leaks memory, but
* called only once.
*/
#ifdef FRONTEND
progname = strdup(nodir_name);
#else
progname = selfpstrdup(nodir_name);
#endif
if (progname == NULL) {
fprintf(stderr, "%s: out of memory\n", nodir_name);
abort();
}
#if defined(__CYGWIN__) || defined(WIN32)
if (strlen(progname) > sizeof(EXE) - 1 && pg_strcasecmp(progname + strlen(progname) - (sizeof(EXE) - 1), EXE) == 0)
progname[strlen(progname) - (sizeof(EXE) - 1)] = '\0';
#endif
return progname;
}
* dir_strcmp: strcmp except any two DIR_SEP characters are considered equal,
* and we honor filesystem case insensitivity if known
*/
static int dir_strcmp(const char* s1, const char* s2)
{
while (*s1 && *s2) {
if (
#ifndef WIN32
*s1 != *s2
#else
pg_tolower((unsigned char)*s1) != pg_tolower((unsigned char)*s2)
#endif
&& !(IS_DIR_SEP(*s1) && IS_DIR_SEP(*s2)))
return (int)*s1 - (int)*s2;
s1++, s2++;
}
if (*s1) {
return 1;
}
if (*s2) {
return -1;
}
return 0;
}
* make_relative_path - make a path relative to the actual binary location
*
* This function exists to support relocation of installation trees.
*
* ret_path is the output area (must be of size MAXPGPATH)
* target_path is the compiled-in path to the directory we want to find
* bin_path is the compiled-in path to the directory of executables
* my_exec_path is the actual location of my executable
*
* We determine the common prefix of target_path and bin_path, then compare
* the remainder of bin_path to the last directory component(s) of
* my_exec_path. If they match, build the result as the part of my_exec_path
* preceding the match, joined to the remainder of target_path. If no match,
* return target_path as-is.
*
* For example:
* target_path = '/usr/local/share/postgresql'
* bin_path = '/usr/local/bin'
* my_exec_path = '/opt/pgsql/bin/postmaster'
* Given these inputs, the common prefix is '/usr/local/', the tail of
* bin_path is 'bin' which does match the last directory component of
* my_exec_path, so we would return '/opt/pgsql/share/postgresql'
*/
static void make_relative_path(
char* ret_path, size_t ret_path_len, const char* target_path, const char* bin_path, const char* my_exec_path)
{
int prefix_len;
int tail_start;
int tail_len;
int i;
* Determine the common prefix --- note we require it to end on a
* directory separator, consider eg '/usr/lib' and '/usr/libexec'.
*/
prefix_len = 0;
for (i = 0; target_path[i] && bin_path[i]; i++) {
if (IS_DIR_SEP(target_path[i]) && IS_DIR_SEP(bin_path[i])) {
prefix_len = i + 1;
} else if (target_path[i] != bin_path[i]) {
break;
}
}
if (prefix_len == 0) {
goto no_match;
}
tail_len = strlen(bin_path) - prefix_len;
* Set up my_exec_path without the actual executable name, and
* canonicalize to simplify comparison to bin_path.
*/
strlcpy(ret_path, my_exec_path, ret_path_len);
trim_directory(ret_path);
canonicalize_path(ret_path);
* Tail match?
*/
tail_start = (int)strlen(ret_path) - tail_len;
if (tail_start > 0 && IS_DIR_SEP(ret_path[tail_start - 1]) &&
dir_strcmp(ret_path + tail_start, bin_path + prefix_len) == 0) {
ret_path[tail_start] = '\0';
trim_trailing_separator(ret_path);
join_path_components(ret_path, ret_path, target_path + prefix_len);
canonicalize_path(ret_path);
return;
}
no_match:
strlcpy(ret_path, target_path, ret_path_len);
canonicalize_path(ret_path);
}
* get_share_path
*/
void get_share_path(const char* my_exec_path, char* ret_path)
{
make_relative_path(ret_path, MAXPGPATH, PGSHAREDIR, PGBINDIR, my_exec_path);
}
* get_etc_path
*/
void get_etc_path(const char* my_exec_path, char* ret_path, size_t ret_path_len)
{
make_relative_path(ret_path, ret_path_len, SYSCONFDIR, PGBINDIR, my_exec_path);
}
* get_include_path
*/
void get_include_path(const char* my_exec_path, char* ret_path)
{
make_relative_path(ret_path, MAXPGPATH, INCLUDEDIR, PGBINDIR, my_exec_path);
}
* get_pkginclude_path
*/
void get_pkginclude_path(const char* my_exec_path, char* ret_path)
{
make_relative_path(ret_path, MAXPGPATH, PKGINCLUDEDIR, PGBINDIR, my_exec_path);
}
* get_includeserver_path
*/
void get_includeserver_path(const char* my_exec_path, char* ret_path)
{
make_relative_path(ret_path, MAXPGPATH, INCLUDEDIRSERVER, PGBINDIR, my_exec_path);
}
* get_lib_path
*/
void get_lib_path(const char* my_exec_path, char* ret_path)
{
make_relative_path(ret_path, MAXPGPATH, LIBDIR, PGBINDIR, my_exec_path);
}
* get_pkglib_path
*/
void get_pkglib_path(const char* my_exec_path, char* ret_path)
{
make_relative_path(ret_path, MAXPGPATH, PKGLIBDIR, PGBINDIR, my_exec_path);
}
* get_locale_path
*/
void get_locale_path(const char* my_exec_path, char* ret_path)
{
make_relative_path(ret_path, MAXPGPATH, LOCALEDIR, PGBINDIR, my_exec_path);
}
* get_doc_path
*/
void get_doc_path(const char* my_exec_path, char* ret_path)
{
make_relative_path(ret_path, MAXPGPATH, DOCDIR, PGBINDIR, my_exec_path);
}
* get_html_path
*/
void get_html_path(const char* my_exec_path, char* ret_path)
{
make_relative_path(ret_path, MAXPGPATH, HTMLDIR, PGBINDIR, my_exec_path);
}
* get_man_path
*/
void get_man_path(const char* my_exec_path, char* ret_path)
{
make_relative_path(ret_path, MAXPGPATH, MANDIR, PGBINDIR, my_exec_path);
}
* get_home_path
*
* On Unix, this actually returns the user's home directory. On Windows
* it returns the openGauss-specific application data folder.
*/
bool get_home_path(char* ret_path, size_t sz)
{
#ifndef WIN32
char pwdbuf[BUFSIZ];
struct passwd pwdstr;
struct passwd* pwd = NULL;
(void)syscalllockAcquire(&getpwuid_lock);
if (pqGetpwuid(geteuid(), &pwdstr, pwdbuf, sizeof(pwdbuf), &pwd) != 0) {
(void)syscalllockRelease(&getpwuid_lock);
return false;
}
strlcpy(ret_path, pwd->pw_dir, sz);
(void)memset_s(pwd, sizeof(struct passwd), 0, sizeof(struct passwd));
(void)syscalllockRelease(&getpwuid_lock);
return true;
#else
char* tmppath = NULL;
* Note: We use getenv here because the more modern
* SHGetSpecialFolderPath() will force us to link with shell32.lib which
* eats valuable desktop heap.
*/
tmppath = gs_getenv_r("APPDATA");
if (tmppath == NULL) {
return false;
}
int rc = snprintf_s(ret_path, sz, sz - 1, "%s/postgresql", tmppath);
#ifdef FRONTEND
securec_check_ss_c(rc, "\0", "\0");
#else
securec_check_ss(rc, "\0", "\0");
#endif
return true;
#endif
}
* get_parent_directory
*
* Modify the given string in-place to name the parent directory of the
* named file.
*
* If the input is just a file name with no directory part, the result is
* an empty string, not ".". This is appropriate when the next step is
* join_path_components(), but might need special handling otherwise.
*
* Caution: this will not produce desirable results if the string ends
* with "..". For most callers this is not a problem since the string
* is already known to name a regular file. If in doubt, apply
* canonicalize_path() first.
*/
void get_parent_directory(char* path)
{
trim_directory(path);
}
* trim_directory
*
* Trim trailing directory from path, that is, remove any trailing slashes,
* the last pathname component, and the slash just ahead of it --- but never
* remove a leading slash.
*/
static void trim_directory(char* path)
{
char* p = NULL;
path = skip_drive(path);
if (path[0] == '\0') {
return;
}
for (p = path + strlen(path) - 1; IS_DIR_SEP(*p) && p > path; p--)
;
for (; !IS_DIR_SEP(*p) && p > path; p--)
;
for (; p > path && IS_DIR_SEP(*(p - 1)); p--)
;
if (p == path && IS_DIR_SEP(*p))
p++;
*p = '\0';
}
* trim_trailing_separator
*
* trim off trailing slashes, but not a leading slash
*/
static void trim_trailing_separator(char* path)
{
char* p = NULL;
path = skip_drive(path);
p = path + strlen(path);
if (p > path)
for (p--; p > path && IS_DIR_SEP(*p); p--)
*p = '\0';
}
* This function can judge whether the work directory of process of pid of postmaster.pid is
* the current data directory.
*/
#ifndef WIN32
bool IsMyPostmasterPid(pid_t pid, const char* data)
{
#define MAXCMDLEN 256
#define MAXLINELEN 4096
char commandstr[MAXCMDLEN] = {0};
char result[MAXLINELEN] = {0};
char lcdata[MAXLINELEN] = {0};
int len = 0;
FILE* fd = NULL;
int rc = 0;
if (data == NULL) {
return false;
}
rc =
snprintf_s(commandstr, sizeof(commandstr), sizeof(commandstr) - 1, "ls -l /proc/%d/cwd|awk '{print $NF}'", pid);
#ifdef FRONTEND
securec_check_ss_c(rc, "\0", "\0");
#else
securec_check_ss(rc, "\0", "\0");
#endif
fd = popen(commandstr, "r");
if (fd == NULL)
return false;
if (fgets(result, sizeof(result), fd) == NULL) {
pclose(fd);
return false;
}
pclose(fd);
len = strlen(result);
if (len > 0 && result[len - 1] == '\n')
result[len - 1] = '\0';
if (realpath(data, lcdata) == NULL) {
return false;
}
if (!strncmp(result, lcdata, MAXLINELEN))
return true;
return false;
}
#endif